1. Field of the Invention
The present invention relates to grinding barrels for use in pulverizers and to methods of grinding material.
2. Description of the Related Art
For the purpose of assaying core samples obtained by drilling, the core samples are normally firstly broken into pieces and these pieces are then pulverized in a pulverizer.
More particularly, the pulverizer is provided with a grinding barrel comprising an upwardly open, dish-shaped grinding barrel body provided with a circular lid for closing the top of the grinding barrel body and a grinding disk located in the interior of the grinding barrel body. The grinding disk has a peripheral diameter which is less than the internal diameter of the grinding barrel body.
In use, the broken pieces or core material are placed in the interior of the grinding barrel body, together with the grinding disk, and the lid is then fitted onto the grinding barrel body. The assembly of the lid, the grinding barrel body and the grinding barrel disk are then installed in the pulverizer, which rotates the assembly with a circular motion, thus causing the grinding disk to slide around within the grinding barrel body, and the bottom of the grinding barrel, so that the material to be pulverized is crushed and pulverized between the grinding disk and the internal surface of the grinding barrel body.
In conventional grinding barrels, the grinding barrel body has a flat circular bottom surface, and the grinding disk has a flat circular undersurface which slides across the top surface of the bottom of the grinding barrel body. Consequently, the material is pulverized mainly between the peripheral surface of the grinding disk and the annular wall of the grinding barrel body.